Shale gas boom has benefits and risks

Lower energy costs welcomed, but harm to environment feared

A proposal to expand a major local pipeline could bring cheap, plentiful supplies of natural gas to New England from Northeast shale formations, but it also thrusts the region into a raging debate that pits economics against environment, industry against community, and sometimes neighbor against neighbor.

The focus is often on a controversial technique, known as fracking, that pumps chemical-laced, pressurized water deep into the earth to unlock natural gas trapped by shale rock. The technology has helped bring jobs, businesses, and money to poorer communities that desperately need it in places like western Pennsylvania.